Pontiac tempest 1968 Service Manual page 359

6E-10 1968 P O N T I A C SERVICE MANUAL
5. Install stator and connect leads.
PI N
F i g , 6 E - 1 5 Brush Holder
5. If old brushes are to be reused, they must be
thoroughly cleaned with soft dry cloth and must be
completely free of o i l .
DIODES
Diodes are checked by making use of their p r i n ­
ciples of allowing electricity to pass through In only
one direction. Two methods are available:
OHMMETER METHOD
The lowest range scale on ohmmeter should be
used and I t should have 1 1/2 volt cell. T o deter­
mine cell voltage, turn selector to lowest scale,
then connect ohmmeter leads to voltmeter. The
voltmeter w i l l indicate cell voltage.
H E A T S I N K
DIODES
6. If there is any doubt about condition of brush
springs, they should be replaced.
7. Install spring and brushes Into brush holder
(they should slide In and out without binding). Insert
straight wood or plastic toothpick (to prevent
scratching brush face) into hole at bottom of holder
to retain brushes.
1. With stator disconnected, check a diode i n heat
sink by connecting one of ohmmeter leads to heat
sink, and other ohmmeter lead to diode lead and
note reading (Fig. 6E-16).
8. Attach brush holder into end frame, noting
carefully stack-up of parts as shown In Fig. 6E-15.
Allow wood or toothpick to protrude through hole i n
end frame and install stator lead to strap attaching
nut and washer.
SLIP RING END FRAME BEARING AND SEAL
1. With stator removed, press out bearing and
seal with tube or collar that just fits Inside end
frame housing. Press from outside of housing t o ­
ward inside. Support Inside of frame with hollow
cylinder to allow seal and bearing to pass through.
2. The bearings i n generator are permanently
lubricated and require no lubrication during life of
bearing. If a dry bearing is encountered, do not
attempt to lubricate, as improper lubricant or ex­
cessive amount of lubricant may burn bearing, or
be thrown off and contaminate Inside of generator.
Replace dry, worn or rough bearings with a new
bearing which w i l l be prepacked with proper amount
and type of lubricant.
3. Place flat plate over bearing and press i n f r o m
outside toward Inside of frame until bearing is flush
with outside of end frame. Support Inside of frame
with hollow cylinder to prevent breakage of end
frame. Use extreme care to avoid misalignment or
otherwise placing undue stress on bearing.
4. F r o m inside of frame, insert seal flush against
bearing.
O H M M E T E R O H M M E T E R
(END FRAME) (HEAT SINK)
F i g . 6 E - 1 6 Checking Diodes
2. Reverse ohmmeter leads and note reading.
3. If both readings are very low or very high (read
same), the diode is defective. A good diode w i l l
give one low reading and one high reading.